Three-dimensional fiber-reinforced composites are used as light, strong materials. A three-dimensional fiber-reinforced composite includes a laminate formed by binding a plurality of fiber bundle layers with binding yarns in matrix resin. Thus, the three-dimensional fiber-reinforced composite has the physical characteristics (mechanical characteristic) superior to materials that only include matrix resin. The three-dimensional fiber-reinforced composite is therefore suitable for a structural component. In addition, the binding yarns allow the three-dimensional fiber-reinforced composite to be stronger in the lamination direction than a two-dimensional fiber-reinforced composite.
For example, Patent Document 1 discloses such a three-dimensional fiber-reinforced composite. As shown in FIG. 5, a three-dimensional fiber-reinforced composite 80 of Patent Document 1 includes a flat three-dimensional fabric 86. The three-dimensional fabric 86 includes in-plane direction yarns 83, which include a plurality of warp yarns 81 and a plurality of weft yarns 82, a plurality of out-of-plane direction yarns 84, which are perpendicular to the reference planes of the in-plane direction yarns 83, and a selvage yarn 85, which fixes the out-of-plane direction yarns 84. The three-dimensional fiber-reinforced composite 80 is formed by impregnating the three-dimensional fabric 86 with resin and hardening the resin.